WO1997026376A1 - Composition for inoculating low sulphur grey iron - Google Patents
Composition for inoculating low sulphur grey iron Download PDFInfo
- Publication number
- WO1997026376A1 WO1997026376A1 PCT/GB1997/000073 GB9700073W WO9726376A1 WO 1997026376 A1 WO1997026376 A1 WO 1997026376A1 GB 9700073 W GB9700073 W GB 9700073W WO 9726376 A1 WO9726376 A1 WO 9726376A1
- Authority
- WO
- WIPO (PCT)
- Prior art keywords
- composition
- strontium
- inoculant
- iron
- rare earth
- Prior art date
Links
Classifications
-
- C—CHEMISTRY; METALLURGY
- C21—METALLURGY OF IRON
- C21C—PROCESSING OF PIG-IRON, e.g. REFINING, MANUFACTURE OF WROUGHT-IRON OR STEEL; TREATMENT IN MOLTEN STATE OF FERROUS ALLOYS
- C21C1/00—Refining of pig-iron; Cast iron
- C21C1/10—Making spheroidal graphite cast-iron
- C21C1/105—Nodularising additive agents
-
- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22C—ALLOYS
- C22C37/00—Cast-iron alloys
- C22C37/04—Cast-iron alloys containing spheroidal graphite
Definitions
- This invention relates to a composition for inoculating grey iron and more particularly to a composition for the inoculation of a grey iron having a low sulphur content.
- Inoculation is a process for controlling the solidification behaviour of the austenite/graphite eutectic and suppressing the formation of the austenite/carbide eutectic in grey cast irons.
- the inoculation treatment ensures that the cast iron has a fully grey structure, provided it is done just prior to casting of the iron, and produces benefits such as improved mechanical properties and machineability.
- a variety of inoculants have been used and many of those are based on ferrosilicon alloys. Other commonly used inoculants are alloys or mixtures of such elements as calcium, silicon, graphite, barium, strontium, aluminium, zirconium, cerium, magnesium, manganese and titanium.
- inoculants Although effective in inoculating molten irons having a sulphur content of above 0.04% by weight, are unsatisfactory as inoculants for low sulphur irons having a sulphur content of 0.04% by weight or below.
- GB-A-2093071 describes a method for inoculating molten iron involving the use of a source of sulphur and a reactant which forms a sulphide therewith which sulphide is capable of acting to provide nuclei in the form of graphite from the molten iron.
- the source of sulphur may be sulphur itself or a sulphide mineral such as chalcocite, bornite, chalcopyrite, stannite, iron sulphide or covellite.
- the sulphide forming reactant may be calcium suicide, calcium carbide, a cerium or strontium alloy, a rare earth and/or magnesium.
- ferrosilicon based composition containing rare earths and strontium can be used effectively as an inoculant for low sulphur iron, without the need to increase the sulphur content of the iron during the inoculation treatment, if the amount of each element is controlled within a certain range and the content of any calcium and/or aluminium which is present does not exceed a certain amount.
- composition for inoculating molten grey iron comprising by weight:
- composition comprises by weight:
- the rare earth may be cerium, mischmetall containing nominally 50% by weight cerium and 50% by weight other rare earths or a mixture of cerium and other rare earths.
- the inoculant composition is most preferably free of aluminium and calcium but if these elements are present the amounts should not exceed the limits indicated. Aluminium is, in general, considered to be a harmful constituent in inoculant compositions, and calcium has an adverse reaction with strontium and affects its performance.
- the inoculant composition may be a particulate mixture of ferrosilicon and the other constituents of the composition but it is preferably a ferrosilicon based alloy containing the other constituents.
- the inoculant can be made in any conventional manner with conventional raw materials.
- a molten bath of ferrosilicon is formed to which a strontium metal or strontium silicide is added along with a rare earth.
- a submerged arc furnace is used to produce a molten bath of ferrosilicon.
- the calcium content of this bath is conventionally adjusted to drop the calcium content to below the 0.35% level.
- strontium metal or strontium silicide and a rare earth is added to this is added strontium metal or strontium silicide and a rare earth.
- the additions of the strontium metal or strontium silicide and rare earth to the melt are accomplished in any conventional manner.
- the melt is then cast and solidified in a conventional manner.
- the solid inoculant is then crushed in a conventional manner to facilitate its addition to the cast iron melt.
- the size of the crushed inoculant will be determined by the method of inoculation, for example, inoculant crushed for use in ladle inoculation is larger than the inoculant crushed for use in mould inoculation. Acceptable results for ladle inoculation are found when the solid inoculant is crushed to a size of about 1 cm down.
- An alternative way to make the inoculant is to layer into a reaction vessel a charge of silicon and iron or ferrosilicon, strontium metal or strontium silicide and rare earth and then melt the charge to form a molten bath. The molten bath is then solidified and crushed as described above.
- the silicon content of the inoculant is about 40 to 80% and the remaining per cent or balance after taking into account all other specified elements is iron.
- Calcium will normally be present in the quartz, ferrosilicon and other additives such that the calcium content of the molten alloy will generally be greater than about 0.5%. Consequently, the calcium content of the alloy will have to be adjusted down so that the inoculant will have a calcium content within the specified range. This adjustment is done in a conventional manner.
- the aluminium in the final alloy is also introduced into the alloy as an impurity in the various additives. If desired, it can also be added from any other conventional source of aluminum or aluminum can be refined out of the alloy using conventional techniques.
- strontium in the inoculant is not precisely known. It is believed that the strontium is present in the inoculant in the form of strontium silicide (SrSi 2 ) when the inoculant is made from a molten bath of the various constituents. However, it is believed that any metallic crystallographic form of the strontium is acceptable in the inoculant.
- Strontium metal is not easily extracted from its principal ores, Strontianite, strontium carbonate, (SrC0 3 ) and Celesite, strontium sulphate (SrS0 4 ).
- the inoculant may be produced with either strontium metal or strontium ore depending upon the economics of the entire production process.
- U.S. Patent No. 3333954 discloses a convenient method for making a silicon bearing inoculant containing acceptable forms of strontium wherein the source of strontium is strontium carbonate or strontium sulphate.
- the carbonate and sulphate are added to a molten bath of ferrosilicon.
- the addition of the sulphate is accomplished by the further addition of a flux.
- a carbonate of an alkali metal, sodium hydroxide and borax are disclosed as appropriate fluxes.
- the method of the 3333954 patent encompasses adding a strontium-rich material to a molten ferrosilicon low in calcium and aluminum contaminates at a sufficient temperature and for a sufficient period of time to cause the desired amount of strontium to enter the ferrosilicon.
- U.S. Patent No. 3333954 is incorporated herein by reference and discloses a suitable way to prepare a silicon-bearing inoculant containing strontium to which a rare earth can be added to form the inoculant of the present invention.
- the addition of the rare earth is preferably done after the addition of the strontium, however, the sequence of the addition is not critical so long as the inoculant has the proper amounts of reactive elements.
- the addition of the rare earth is accomplished in any conventional manner.
- the rare earth can come from any conventional source, for example, individual pure rare earth metals, mischmetall, rare earth of cerium silicide and, under appropriate reducing conditions, rare earth ores such as bastnasite or manazite.
- the inoculant be formed from a molten mixture of the different constituents as described hereinbefore, however, the inoculant of the present invention can be made by forming a dry mix or briquette that includes all of the constituents without forming a molten mix of the constituents. It is also possible to use two or three of the constituents in an alloy and then add the other constituents, either in a dry form or as briquettes, to the molten iron bath to be treated. Thus, it is within the scope of this invention to form a silicon-bearing inoculant containing strontium and use it with a rare earth.
- the addition of the inoculant to the cast iron is accomplished in any conventional manner.
- the inoculant is added as close to final casting as possible.
- ladle and stream inoculation are used to obtain very good results.
- Mould inoculation may also be used.
- Stream inoculation is the addition of the inoculant to a molten stream as it is going into the mould.
- the amount of inoculant to add will vary and conventional procedures can be used to determine the amount of inoculant to add. Acceptable results can be obtained by adding about 0.05 to 0.3% of inoculant based on the weight of iron treated when using ladle inoculation.
- An inoculant composition, according to the invention, was produced in the form of a ferrosilicon based alloy comprising by weight:
- This composition was tested as an inoculant for low sulphur iron in comparison with two commercially available inoculants, FOUNDRISIL® and CALBALLOYTM and with a ferrosilicon based alloy containing 2.0% by weight rare earth (1.2% by weight cerium) and 1.0% by weight calcium but no strontium.
- Each of the inoculants was used to inoculate three irons containing three different levels of sulphur, 0.01%, 0.03% and 0.05% by weight.
- RE/Sr denotes the inoculant composition according to the invention and "RE/Ca” denotes the ferrosilicon alloy containing rare earth and calcium but no strontium.
- the graphite morphology was determined by classifying the form and size of the graphite in a polished microspecimen taken from the centre of the bar casting. This was done by comparing the specimen at a standard magnification of 100 diameters with a series of standard diagrams, and allocating letters and numerals to indicate form and size of the graphite based on the system proposed by the American Society for the Testing of Metals, ASTM Specification A247.
- the iron contains a random distribution of flakes of graphite of uniform size. This type of graphite structure forms when a high degree of nucleation exists in the liquid iron, promoting solidification close to the equilibrium graphite eutectic. This is the preferred structure for engineering applications.
- the iron contains fine, undercooled graphites which form in rapidly cooled irons having insufficient graphite nuclei. Although the fine flakes increase the strength of the eutectic, this morphology is undesirable because it prevents the formation of a fully pearlitic matrix.
- the inoculant composition of the invention (RE/Sr) is more effective than the two proprietary inoculants, FOUNDRISIL® and CALBALLOYTM, both of which contain approximately 1% of calcium and 1% barium, even at a lower addition rate, and a low eutectic cell count is maintained for the level of inoculation.
- the RE/Sr composition is still effective but the RE/Ca composition is similar in performance.
- the proprietary barium-containing inoculants show equivalent or better chill removal compared with the RE/Sr composition and the RE/Ca composition is also better.
- An inoculant composition was produced as a ferrosilicon based alloy having the following composition by weight.
- compositions tested were:
- INOCULIN 25® a ferrosilicon based proprietary inoculant containing manganese, zirconium and aluminium.
- SUPERSEED® a ferrosilicon based proprietary inoculant containing nominally 1% strontium and no rare earth.
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- Chemical & Material Sciences (AREA)
- Engineering & Computer Science (AREA)
- Materials Engineering (AREA)
- Metallurgy (AREA)
- Organic Chemistry (AREA)
- Mechanical Engineering (AREA)
- Refinement Of Pig-Iron, Manufacture Of Cast Iron, And Steel Manufacture Other Than In Revolving Furnaces (AREA)
- Sliding-Contact Bearings (AREA)
- Organic Low-Molecular-Weight Compounds And Preparation Thereof (AREA)
- Solid-Sorbent Or Filter-Aiding Compositions (AREA)
- Basic Packing Technique (AREA)
- Micro-Organisms Or Cultivation Processes Thereof (AREA)
- Glanulating (AREA)
- Anti-Oxidant Or Stabilizer Compositions (AREA)
- Compositions Of Macromolecular Compounds (AREA)
- Medicines Containing Antibodies Or Antigens For Use As Internal Diagnostic Agents (AREA)
- Preparation Of Compounds By Using Micro-Organisms (AREA)
- Carbon And Carbon Compounds (AREA)
Priority Applications (9)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
CA002242782A CA2242782C (en) | 1996-01-16 | 1997-01-10 | Composition for inoculating low sulphur grey iron |
JP09515318A JP2000512686A (ja) | 1996-01-16 | 1997-01-10 | 低硫黄ねずみ銑鉄接種用組成物 |
AU13909/97A AU721510B2 (en) | 1996-01-16 | 1997-01-10 | Composition for inoculating low sulphur grey iron |
DE69702045T DE69702045T2 (de) | 1996-01-16 | 1997-01-10 | IMPFmittel für schwefelarmes Graugußeisen |
EP97900322A EP0874916B1 (en) | 1996-01-16 | 1997-01-10 | Composition for inoculating low sulphur grey iron |
DK97900322T DK0874916T3 (da) | 1996-01-16 | 1997-01-10 | Sammensætning til inokulation af svovlfattigt støbejern |
US09/101,294 US6177045B1 (en) | 1996-01-16 | 1997-01-10 | Composition and method for inoculating low sulphur grey iron |
AT97900322T ATE193062T1 (de) | 1996-01-16 | 1997-01-10 | Impflegierung zur bildung von graphit in schwefelarmen graugusseisen |
NO19983258A NO322759B1 (no) | 1996-01-16 | 1998-07-15 | Sammensetning for inokulering av grajern med lavt svovelinnhold |
Applications Claiming Priority (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
GB9600807.3 | 1996-01-16 | ||
GBGB9600807.3A GB9600807D0 (en) | 1996-01-16 | 1996-01-16 | Composition for inoculating low sulphur grey iron |
Publications (1)
Publication Number | Publication Date |
---|---|
WO1997026376A1 true WO1997026376A1 (en) | 1997-07-24 |
Family
ID=10787077
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
PCT/GB1997/000073 WO1997026376A1 (en) | 1996-01-16 | 1997-01-10 | Composition for inoculating low sulphur grey iron |
Country Status (18)
Country | Link |
---|---|
US (1) | US6177045B1 (ru) |
EP (1) | EP0874916B1 (ru) |
JP (1) | JP2000512686A (ru) |
CN (1) | CN1068632C (ru) |
AT (1) | ATE193062T1 (ru) |
AU (1) | AU721510B2 (ru) |
CA (1) | CA2242782C (ru) |
DE (1) | DE69702045T2 (ru) |
DK (1) | DK0874916T3 (ru) |
ES (1) | ES2146075T3 (ru) |
GB (1) | GB9600807D0 (ru) |
ID (1) | ID17336A (ru) |
MY (1) | MY116840A (ru) |
NO (1) | NO322759B1 (ru) |
PT (1) | PT874916E (ru) |
RU (1) | RU2155819C2 (ru) |
WO (1) | WO1997026376A1 (ru) |
ZA (1) | ZA97254B (ru) |
Cited By (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
WO1999029911A1 (en) * | 1997-12-08 | 1999-06-17 | Elkem Asa | Cast iron inoculant and method for production of cast iron inoculant |
CN1044392C (zh) * | 1996-02-05 | 1999-07-28 | 田福元 | 一种用于铸铁冶炼的复合添加剂 |
WO2006049525A1 (fr) * | 2004-11-04 | 2006-05-11 | Dynin, Anton Yakovlevich | Alliage permettant de modifier de la fonte |
US11486011B2 (en) | 2017-12-29 | 2022-11-01 | Elkem Asa | Cast iron inoculant and method for production of cast iron inoculant |
Families Citing this family (10)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
FR2838134B1 (fr) * | 2002-04-03 | 2005-02-25 | Pechiney Electrometallurgie | Pion inoculant anti microretassures pour traitement des fontes de moulage |
US20070023106A1 (en) * | 2003-07-16 | 2007-02-01 | Milan Lampic-Oplander | Cast iron material |
US9724250B2 (en) * | 2012-11-30 | 2017-08-08 | Kimberly-Clark Worldwide, Inc. | Unitary fluid intake system for absorbent products and methods of making same |
RU2553125C1 (ru) * | 2013-11-13 | 2015-06-10 | Федеральное государственное бюджетное образовательное учреждение высшего профессионального образования "Нижегородский государственный технический университет им. Р.Е. Алексеева", НГТУ | Модифицирующая смесь |
WO2016186094A1 (ja) * | 2015-05-18 | 2016-11-24 | 東芝機械株式会社 | 鋳鉄溶湯処理方法 |
CN105385932A (zh) * | 2015-10-26 | 2016-03-09 | 无锡市永亿精密铸造有限公司 | 精密铸造的液压泵壳体 |
US10767238B2 (en) * | 2016-04-15 | 2020-09-08 | Elkem Asa | Gray cast iron inoculant |
MX2016010930A (es) * | 2016-08-23 | 2017-04-03 | Arbomex S A De C V | Proceso de fabricacion de arbol de levas con componente funcional como inserto de ensamble y el arbol de levas obtenido con el mismo. |
CN108950120A (zh) * | 2018-06-29 | 2018-12-07 | 石家庄北科德瑞冶金材料有限公司 | 一种铸铁用硅-镧-锶孕育剂及其制备方法 |
CN111363876A (zh) * | 2020-04-28 | 2020-07-03 | 共享装备股份有限公司 | 一种用于灰铸铁喂线孕育的孕育线配方及生产工艺 |
Citations (5)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
GB1179083A (en) * | 1967-02-10 | 1970-01-28 | Foote Mineral Co | Production of Grey Cast Iron |
US4224064A (en) * | 1979-04-27 | 1980-09-23 | Union Carbide Corporation | Method for reducing iron carbide formation in cast nodular iron |
US4581203A (en) * | 1983-06-28 | 1986-04-08 | Skw Trostberg Aktiengesellschaft | Process for the manufacture of ferrosilicon or silicon alloys containing strontium |
DE3809315A1 (de) * | 1988-03-19 | 1989-10-05 | Sueddeutsche Kalkstickstoff | Impflegierung auf basis von ferrosilicium oder silicium, verfahren zu ihrer herstellung und ihre verwendung |
EP0357521A1 (fr) * | 1988-08-12 | 1990-03-07 | Pechiney Electrometallurgie | Procédé d'obtention de fonte à graphite sphéroidal |
-
1996
- 1996-01-16 GB GBGB9600807.3A patent/GB9600807D0/en active Pending
-
1997
- 1997-01-07 MY MYPI97000050A patent/MY116840A/en unknown
- 1997-01-10 EP EP97900322A patent/EP0874916B1/en not_active Expired - Lifetime
- 1997-01-10 JP JP09515318A patent/JP2000512686A/ja active Pending
- 1997-01-10 DK DK97900322T patent/DK0874916T3/da active
- 1997-01-10 DE DE69702045T patent/DE69702045T2/de not_active Expired - Lifetime
- 1997-01-10 AT AT97900322T patent/ATE193062T1/de active
- 1997-01-10 ES ES97900322T patent/ES2146075T3/es not_active Expired - Lifetime
- 1997-01-10 US US09/101,294 patent/US6177045B1/en not_active Expired - Lifetime
- 1997-01-10 CN CN97192977A patent/CN1068632C/zh not_active Expired - Lifetime
- 1997-01-10 RU RU98115298/02A patent/RU2155819C2/ru active
- 1997-01-10 AU AU13909/97A patent/AU721510B2/en not_active Ceased
- 1997-01-10 WO PCT/GB1997/000073 patent/WO1997026376A1/en active IP Right Grant
- 1997-01-10 CA CA002242782A patent/CA2242782C/en not_active Expired - Lifetime
- 1997-01-10 PT PT97900322T patent/PT874916E/pt unknown
- 1997-01-13 ZA ZA97254A patent/ZA97254B/xx unknown
- 1997-01-16 ID IDP970108A patent/ID17336A/id unknown
-
1998
- 1998-07-15 NO NO19983258A patent/NO322759B1/no not_active IP Right Cessation
Patent Citations (5)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
GB1179083A (en) * | 1967-02-10 | 1970-01-28 | Foote Mineral Co | Production of Grey Cast Iron |
US4224064A (en) * | 1979-04-27 | 1980-09-23 | Union Carbide Corporation | Method for reducing iron carbide formation in cast nodular iron |
US4581203A (en) * | 1983-06-28 | 1986-04-08 | Skw Trostberg Aktiengesellschaft | Process for the manufacture of ferrosilicon or silicon alloys containing strontium |
DE3809315A1 (de) * | 1988-03-19 | 1989-10-05 | Sueddeutsche Kalkstickstoff | Impflegierung auf basis von ferrosilicium oder silicium, verfahren zu ihrer herstellung und ihre verwendung |
EP0357521A1 (fr) * | 1988-08-12 | 1990-03-07 | Pechiney Electrometallurgie | Procédé d'obtention de fonte à graphite sphéroidal |
Cited By (6)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN1044392C (zh) * | 1996-02-05 | 1999-07-28 | 田福元 | 一种用于铸铁冶炼的复合添加剂 |
WO1999029911A1 (en) * | 1997-12-08 | 1999-06-17 | Elkem Asa | Cast iron inoculant and method for production of cast iron inoculant |
CN1085256C (zh) * | 1997-12-08 | 2002-05-22 | 埃尔凯姆公司 | 铸铁孕育剂及铸铁孕育剂的生产方法 |
WO2006049525A1 (fr) * | 2004-11-04 | 2006-05-11 | Dynin, Anton Yakovlevich | Alliage permettant de modifier de la fonte |
EA008521B1 (ru) * | 2004-11-04 | 2007-06-29 | Общество С Ограниченной Ответственностью «Промышленная Компания "Новые Перспективные Продукты"» | Сплав для модифицирования чугуна |
US11486011B2 (en) | 2017-12-29 | 2022-11-01 | Elkem Asa | Cast iron inoculant and method for production of cast iron inoculant |
Also Published As
Publication number | Publication date |
---|---|
CN1068632C (zh) | 2001-07-18 |
GB9600807D0 (en) | 1996-03-20 |
AU1390997A (en) | 1997-08-11 |
DE69702045T2 (de) | 2001-03-08 |
US6177045B1 (en) | 2001-01-23 |
ZA97254B (en) | 1997-07-18 |
RU2155819C2 (ru) | 2000-09-10 |
AU721510B2 (en) | 2000-07-06 |
ES2146075T3 (es) | 2000-07-16 |
DE69702045D1 (de) | 2000-06-21 |
NO322759B1 (no) | 2006-12-04 |
JP2000512686A (ja) | 2000-09-26 |
DK0874916T3 (da) | 2000-11-20 |
ATE193062T1 (de) | 2000-06-15 |
PT874916E (pt) | 2000-08-31 |
MY116840A (en) | 2004-04-30 |
NO983258D0 (no) | 1998-07-15 |
EP0874916A1 (en) | 1998-11-04 |
CA2242782C (en) | 2003-06-17 |
ID17336A (id) | 1997-12-18 |
NO983258L (no) | 1998-07-15 |
CA2242782A1 (en) | 1997-07-24 |
EP0874916B1 (en) | 2000-05-17 |
CN1213408A (zh) | 1999-04-07 |
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